化學迴圈燃燒技術與傳統之碳捕捉技術相比，前者顯現出了較優越的性能，不僅能夠直接在燃料反應器中獲得高純度的CO2，且空氣汙染物減量的部分也有相當優異的表現。對於硫化物而言，在化學迴圈煤炭燃燒系統中，因載氧體的供氧，使得產物中主要的硫化物種類為SO2，而且本實驗所製備之載氧體又可作為硫化物的吸收劑，近一步地減少了SO2的產量。對於氮化物而言，因化學迴圈系統避免了O2與N2在高溫環境下的直接接觸，從而大幅度的減少了NOx的生成。
本實驗使用Ca(OH)2與Fe2O3為原料製備CaO/Fe2O3之載氧體。載氧體製備參數以反應性、循環性與機械強度作為考量，Ca(OH)2與Fe2O3以重量比為3：7的比例混合，粒徑為14目(1.2-1.4 mm)且鍛燒溫度為800 °C時擁有較佳的效能。
在硫化與再生程序中，透過氧氣再生硫化之載氧體時將產生副產物CaSO4，使得載氧體無法完全被氧化，間接地造成性能的下降。本實驗利用20% H2作為CaSO4的移除劑並探討氧化過程中氧氣濃度對於CaSO4的產量之影響。實驗結果顯示出氧氣濃度為16%時是較理想之反應條件。
對於載氧體的還原動力學分析，本實驗以多種氣固反應模型進行擬合，其中以2-D diffusion (D2) 模型最能完整的描述載氧體分別在H2與CO環境下之還原情形，並得出H2與CO的還原活化能分別為35.42 kJ/mol與45.98 kJ/mol。對於煤炭燃燒的動力學分析，以zero-order model (F0) 模型最能完整的描述煤炭的燃燒情形，並得出CO2與SO2的生成活化能分別為20.04 kJ/mol與11.47 kJ/mol。
本實驗以固定床反應器實行化學迴圈煤炭燃燒系統，實驗結果顯示，以體積濃度20%之CO2作為固體燃料之氣化劑，載氧體與煤炭的重量比為1.8且操作溫度為900 °C時具有較優異之燃燒效能與硫化物減量效益。與純煤炭熱裂解實驗做比較，化學迴圈程序可大幅度地降低SO2的產率。

Compare to traditional carbon capture and storage (CCS) technology, chemical looping combustion (CLC) has an outstanding performance. It not only can produce a high purity CO2 from the fuel reactor but also functions as sulfur sorbent. In addition, CLC process avoids the contact between N2 and O2 in a high temperature which decreases the formation of NOx indirectly.
In this research, Ca(OH)2 and Fe2O3 were as a precursor to fabricate the CaO/Fe2O3 oxygen carriers. The result indicated that considered the reactivity, recyclability and mechanical strength of material, the optimal parameters were an Ca(OH)2 and Fe2O3 weight ratio of 3:7, a particle size of 14 mesh (1.2-1.4 mm) and a calcination temperature of 800 °C.
For the desulfurization-regeneration process, an undesired product, CaSO4 was produced during the regeneration process by oxygen. It would cause the oxygen carriers to not be completely oxidized which decreased the performance of oxygen carriers. This research attempted to remove CaSO4 by 20% H2 and discussed the partial pressure of oxygen in the regeneration step. The result indicated that 16% O2 was optimal.
For the reduction kinetic analysis of CaFe-378 oxygen carrier, 2-D diffusion model (D2) could describe the reduction process completely with both H2 or CO atmosphere. And the reduction activation energy of H2 and CO was 35.42 kJ/mol and 45.98 kJ/mol, respectively. For the combustion of coal, the zero-order model (F0) could describe the combustion process completely. The formation activation energy of CO2 and SO¬2 was 20.04 kJ/mol and 11.47 kJ/mol, respectively.
A fixed bed reactor was introduced to carry on the CLC process, the result indicated that CO2, the gasification agent, was optimal at a volume concentration of 20%. The optimal OC/C weight ratio was equal to 1.8 and the optimal operating temperature was 900 °C.
Compare with the coal pyrolysis without oxygen carriers, the CLC process using CaFe-378 as oxygen carrier could reduce the yield of SO2 effectively.

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